DROP TEST EXPERIMENTAL RESULTS OF 1/3 SCALE MODEL FOR TK TYPE TRANSPORT AND STORAGE CASK

Dry storage system using spent fuel casks is focused on in these days and demand of storage using casks is expected to be strong increasingly. One of the most important design elements for safety of cask is its integrity under 9m drop tests. Drop tests using 1/3 scale model for TK type transport and storage cask were performed in order to confirm its structural integrity and establish suitable safety analysis method on 9m drop test conditions. The height of drop tests is 9m and the drop tests were conducted with 4 different conditions such as horizontal, vertical, corner and slap-down. It is confirmed by these drop tests that the impact accelerations for all conditions are less than those of analysis conditions for 9m drop tests in the safety analysis of TK-69 and that the deformations of the shock absorbing covers are within the deforming limitation. The ratio of the maximum acceleration of the dummy content to the shell of 1/3 scale model is 0.97-1.04 for horizontal condition and 0.92-1.42 for vertical condition. The maximum acceleration of slap-down condition is a little larger than that of horizontal condition and the maximum ratio is 1.20 for the primary lid. These drop tests result in the structural integrity of TK type cask. And these test results are used for confirming validity of the safety analysis procedures on 9m drop test conditions for TK type casks.